1. Technical Field
The present disclosure relates generally to barcode imaging and laser scanning systems. In particularly, the present disclosure relates to barcode imaging and laser scanning systems having improved visual decoding indication.
2. Description of the Prior Art
Handheld barcode systems that use linear sensor arrays or a laser beam to capture an image of a single line across a barcode are common, such as used in point-of-sale systems. A barcode scanner of a barcode imaging system usually includes an illumination system which shines light on the barcode in the area where an image sensor is aimed, so as to improve the quality of the image that is captured by the image sensor and to eliminate total dependency on ambient light conditions.
For best performance, typically in barcode imaging systems, the light projected from the illumination system is concentrated as much as possible on the line that is scanned by the sensor array of the barcode scanner. This has the visual appearance of a bright thick line that is projected out of the front of the barcode scanner onto the barcode being imaged. This visible line performs the secondary function of creating a visual indication of where the image sensor is aimed, allowing the user to position the barcode scanner so that the visible line is on the barcode to be imaged.
Typically, the illumination system in a barcode imaging system turns on when a trigger switch of the barcode scanner is pressed, and the illumination system turns off as soon as the barcode scanner decodes a barcode, or when the trigger is released, or after a predetermined time period has elapsed. If the barcode scanner turns off due to successfully reading a barcode, the extinguishing of the illumination system of the barcode imaging system is accompanied with an audible indication from a speaker or beeper, and, in most cases, also with the illumination of an indicator LED in the housing of the barcode scanner.
Although this combination of actions upon a successful decode has generally proven to provide adequate user feedback that a decode has been achieved by a barcode imaging system, there is room for improvement. There is also room for improvement for laser barcode scanning systems where generally the actions performed after a successful decode is an audible indication from a speaker or beeper and/or the turning off of a laser beam system.
However, it has been found that most users depend almost entirely on the audible indication to know when a decode has occurred in prior art barcode imaging and laser barcode scanning systems. The audible indicator, however, is not always adequate, such as, for example, in noisy environments, or where it must be turned off due to the desirability to maintain silence or where the beeping sound is annoying or distracting to people nearby.
In these environments, users often rely on the turning on and turning off of the illumination system or the laser beam system as an indication of a decode in barcode imaging and laser barcode scanning systems, respectively. This, however, is not foolproof as the illumination system or laser beam system might have been turned off for reasons other than a decode, such as the elapsed time limit having been exceeded or because of the operator accidentally relaxing pressure on the trigger switch, both of which would result in the illumination system or laser beam system being turned off without the barcode having been decoded. Whenever this occurs, the integrity of the data being collected by the imaging or laser scanning process is compromised. It is therefore important to find a non-ambiguous method to indicate when a barcode scanner of barcode imaging and laser barcode scanning systems has decoded a barcode.
One attempt to solve this problem has been to install an additional optical system in a handheld barcode scanner in order to project a spot of light out the front of the scanner whenever a decode occurs. When a user sees this spot of light, the user will know that a barcode has been decoded. While this is an improvement over prior art barcode scanner designs, it still has several shortcomings. One problem is that the spot of light is generally small, and due to tolerances in the optical system that projects it, the spot of light does not always shine exactly at the center of the reading field of the barcode scanner. The result of the latter is that the spot of light will sometimes miss the object being scanned, especially if the object is small. If the spot of light misses the object, the user will typically not see the spot of light and might assume the barcode was not decoded, resulting in a second unwanted attempt to scan the same barcode. Further, another problem is that the additional optical system for projecting the spot of light adds cost and size to the barcode scanner.
A need therefore exists for a barcode imaging/decoding system having an improved visual decoding indication that overcomes the shortcomings of prior art barcode imaging/decoding systems, as well as prior art laser barcode scanning/decoding systems.
Additionally, with respect to prior art barcode imaging systems, as well as laser barcode scanning systems, many prior art barcode scanners of these systems are designed to be used in a hands-free mode where they are placed in a stand or cradle, as opposed to being held by the user's hand. Such prior art barcode scanners when placed in the stand are automatically placed in an automatic, continuous scanning mode, so that there is no need to press a trigger switch to image or laser scan a barcode that is positioned in front of the barcode scanner.
Many barcode imaging scanners when used in the hands-free mode have their illumination system turned off during the time that no barcode is being presented to the barcode scanner. The imaging barcode scanner continues to process the signal from the sensor array, which can provide a useful, if not optimum signal even with the barcode scanner's illumination system being deactivated. Since the illumination system is not activated during this time, the barcode scanner depends on ambient light in order to capture images of sufficient quality. In this mode, the signal from the image sensor is analyzed to determine if there is a change in the signal from one scan to the next. If a change of sufficient magnitude is detected, it is assumed that a user has placed a barcode in front of the barcode scanner. The barcode scanner, therefore, turns on its illumination system to improve signal quality so as to allow decoding of the barcode.
A problem with such prior art barcode imaging systems, is that before an object is placed in front of the hands-free barcode scanner, the illumination system is turned off, so there is no visual guide for the user to know exactly where the barcode should be positioned for imaging. The user guesses where the visible line will be projected from the barcode scanner, moves the barcode to the imaginary location, and when the illumination system finally turns on, the user corrects or adjusts the location of the barcode as necessary to bring it to the proper location for imaging. Obviously, it would be better if it was clearly indicated to the user where the barcode should be positioned, so that the barcode can be positioned in the proper location by the user.
A solution to this problem is to provide hands-free barcode imaging scanners with the optical system described above which projects the spot of light. However, instead of projecting the spot of light to indicate the occurrence of a decode as described above, when operating the barcode scanner in the hands-free mode the optical system continuously projects the spot of light, thereby giving guidance to the user where to position the barcode. Accordingly, the addition of the optical system to a hands-free barcode scanner enables better operation of the scanner, but it necessitates for the barcode scanner to bear the extra size and cost of the optical system that projects the spot of light. Additionally, since the spot of light is continuously projected, it can no longer serve the other function of visually indicating a decode by turning on only after a decode has occurred.
A need therefore exists for an improved visual decoding indication when operating a barcode scanner of a barcode imaging/decoding system in a hands-free mode that overcomes the shortcomings of the prior art barcode imaging/decoding systems. A need also exists for an improved visual decoding indication when operating a barcode scanner of a laser barcode scanning/decoding system in a hands-free mode.